LEBANON — Dartmouth researchers are making promising advances in an emerging technique in diagnostic imaging for breast cancer, but they need more women to participate in clinical trials.
Engineers and radiologists at the Norris Cotton Cancer Center at Dartmouth-Hitchcock in Lebanon have been developing new approaches in the conjoined use of MRI and near-infrared spectroscopy, or NIRS, for the past eight years, said Dr. Shudong Jiang, an associate professor at the Thayer School of Engineering at Dartmouth.
The technique of combing an MRI with NIRS may benefit women whose mammograms showed an abnormality and require further testing to rule out cancer before an invasive biopsy is conducted to look for tumors.
“These contrasting imaging with the MRI and NIRS can give a much better prediction of what kind of tumor you have,” Jiang said.
Currently, the technique is only 86 percent accurate in predicting that a patient has a malignant or benign tumor, she said. The Dartmouth researchers aim to increase that to 90 percent or more.
The researchers also are working on a standalone NIRS imaging that could eventually replace the mammogram, which exposes patients to radiation, she said.
The MRI/NIRS needs to be able to adapt to an individual’s body size as well as accommodate a range of cup sizes.
The MRI/NIRS offers specific advantages to women with dense breasts, Jiang said. Studies show women with dense breasts are more likely to develop and die from breast cancer; however, mammogram results of women with dense breast (tissue) are hard to read, she said.
“A dense breast is harder for a radiologist to ‘see through’ when using traditional imaging equipment, which lacks the sensitivity to penetrate the dense tissue. Standard breast screening is effective 77-97 percent of the time in a normal breast, but falls to 63-89 percent when a breast is dense,” according to a press release from the Dartmouth researchers. “Prior approaches for MRI/NIRS used parallel plates and relied on custom breast molds for each patient. Biomedical engineers from the Thayer School of Engineering at Dartmouth developed a new, more flexible, convenient, and comfortable approach. They designed a set of eight light-transmitting cables that can be adjusted to surround the breast with light tension. A woman lies on her stomach and the breast hangs through the holes of the MRI/NIRS breast coil. The procedure is nearly identical to a clinical MRI.”
A few years ago, eight women participated in a trial of the new design.
“We found that the new interface allowed us to target lesions more effectively than ever before, Michael A. Mastanduno, researcher at the Thayer School, said in the press release. “Set up time was faster and images were of higher quality.”
“Hard to see areas” such as the outside area of the breast near the armpit gets increased coverage with the Dartmouth designed MRI/NIRS.
“This work is a huge improvement on previous designs of MRI/NIRS systems. All breast sizes and lesion locations can now be effectively imaged. Though there is more work to be done, this technology is promising for improving MRI’s ability to distinguish cancer from benign abnormalities,” Mastanduno said.
Last year, the study went to China where over a three-and-half month period 60 Chinese women going through the breast cancer diagnostic process participated.
The Dartmouth researchers would like to continue its clinical trials in the U.S., but the Upper Valley area has a smaller population. Additionally, American women in the throes of a breast cancer diagnosis are usually too upset to participate in a clinical trial. These women want to expedite their diagnosis, Jiang said.
“The time window is really limited and when the women just don’t know if they might have cancer; they will be mentally anxious, so it’s very difficult to find” women to participate, Jiang said.
The results of the study in China were favorable, Jiang said, and will be reported in the journal Academic Radiology in February.